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    <meta charset="UTF-8">
    <title>DOM 遍历</title>
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<body>
    <h1>DOM 遍历实例</h1>
    <section>
        <ul>
            <li>1.1</li>
            <li>1.2</li>
            <li>
                1.3
                <ul>
                    <li>2.1</li>
                    <li>2.2</li>
                    <li>2.3</li>
                    <li>2.4</li>
                </ul>
            </li>
            <li>1.4</li>
        </ul>
    </section>
</body>
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